scubaseason

Thornback Ray

Raja clavata

Sighting evidence at Sound of Mull, Oban

Thornback rays rest on sandy patches among boulders throughout the Sound, perfectly camouflaged against the mixed substrate and detectable only by their outline and the slight movement of spiracles on the dorsal surface. They feed on crustaceans and small fish buried in or moving over the seabed. Female rays deposit characteristic mermaid's purse egg cases among kelp holdfasts, and empty cases are commonly found on dives throughout summer and autumn.

Evidence at this site

No confirmed records on file at this site

Thornback Ray is listed as a curated species here based on historical reports.

How is this calculated?

Sighting evidence is compiled from iNaturalist observation records within a set proximity radius, filtered for quality-grade observations. “Last confirmed” is the date of the most recent research-grade record. Record count covers a rolling 24-month window. Confidence reflects record count, recency, and consistency of seasonal signal.

Also seen at other sites